Twilight has been doing a bit o’ research...

Why does the cutie mark appear on the clothing rather than as a marking on the body?
Do cutie marks serve a different purpose in the human world? What’s the significance?
Why do some humans have marks on their clothes, whereas others do not?
Would they be considered “blank flanks” as ponies?
Do said humans have the cutie marks somewhere hidden on their bodies?
Would it be an artificial mark like a “tattoo”, or a biological one like a birthmark?
Is there some genetic or biological properties to the clothing that appears when a human (who was a pony prior) enters the portal?
Is it magical rather than biological?
When a human magically undergoes a “pony up” and spawns ears, tails, wings, etc., wouldn’t it be natural for a cutie mark to appear somewhere on the body as well?

So many questions raise new ones…
Twilight being the adamantly curious soul she is decides to delve deeper into the cutie mark mystery. For starters, by graphing the general area of her own skin with a crude reconstruction of it using a sharpie. From there, perhaps she might be able to further demonstrate her apparent underlying conundrum going forward.

I've heard some people say that the relative position of the cutie mark on a pony is on the rump or buttcheek, but to be honest, calling it somewhere nearer to the lower hip area just feels more natural to me, especially of we're talking where it'd be located on a humanized pony.
What do you guys think? Would a cutie mark be located on the backside or the hip? (or on the facial area, as most promotional art seems to depict)

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